在此首次通過水熱法成功製備了石墨烯量子點（Er-GQDs），用於增強人血清中Fe3+的檢測。 GQDs僅在乳糖存在下製備。然後將Er3 +離子以1:50的比例添加到GQDs溶液中。 TEM圖像清楚地表明，Er-GQDs的納米顆粒尺寸在1.9 – 5 nm範圍內。 XRD和XPS清楚地表明Er3 +已成功整合到GQDs晶格中。有趣的是，摻Er3+的GQDs在360 – 730 nm的波長下均具有上轉換和下轉換的光學特性。 730 nm的上轉換和360 nm的下轉換均可產生440 nm的激發波長，這可以靈敏地選擇性檢測Fe3 +。在這項研究中，證據清楚地顯示了飲用水和人血清中Fe3+的出色靈敏度，LD50 1mg mL-1的MTT結果證明了這一點，線性範圍從40 nM – 8 µM，LOD 11.2 nM和1.2 µM – 10觀察到LOD為336 nM的µM。此外，當在波長360 nm下轉換時，觀察到Er-GQDs的良好分析性能。結果清楚地表明，Er-GQDs具有出色的光學性能，這可以為摻雜鑭系元素的GQDs打開通往各種應用的大門。
關鍵詞：鐵離子；石墨烯量子點；鑭系元素；熒光；選擇性。

Herein, erbium-doped graphene quantum dots (Er-GQDs) have been successfully fabricated for the first time with a hydrothermal method for the enhanced detection of Fe3+ in human serum. GQDs were simply prepared in the presence of lactose. Er3+ ions were then added to the GQDs solution at a ratio of 1:50. The TEM image clearly showed that the nanoparticles size of Er-GQDs was in the range of 1.9 – 5 nm. XRD and XPS clearly indicated the successful incorporation of Er3+ into GQD lattice. Interestingly, the Er3+-doped GQDs exhibit both up-conversion and down-conversion optical properties in the wavelength of 360 – 730 nm. Both the up-conversion at 730 nm and down-conversion at 360 nm can produce the excitation wavelength of 440 nm, which can be sensitive and selective detection of Fe3+. In this study, the evidences clearly show the outstanding sensitivity of Fe3+ in the drinking water and human serum proved with MTT results at LD50 1mg mL-1, a good linear range from 40 nM – 8 µM with LOD 11.2 nM and 1.2 µM – 10 µM with LOD 336 nM were observed. In addition, good analytical performance of Er-GQDs was observed when the down-conversion at wavelength 360 nm. Results clearly indicated the excellent optical properties of Er-GQDs, which can open a gateway to various applications using lanthanide-doped GQDs.
Keywords: ferric ions, graphene quantum dots (GQDs), lanthanide, fluorescence, selectivity.

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